Pipe lining method and machine



y 1950 J. M. CROM 2,513,2fi9

PIPE mum: METHOD AND MACHINE Filed Nov. 20, 1946 i uni-PX U3 l .l

INVENTOR. JOHN M. CROM BY K w- 10m a ATTORNEYS Patented July 4, 1950 PIPE LINING METHOD AND DIACHINE John M. Crom, Washington, D. 0., assignor to Preload Enterprises, Inc., a. corporation of Delaware Application November 20, 1946, Serial No. 711,032

Claims.

This invention relates particularly to the lining of large pipes, irrigation ditches, etc. with cementitious composition as shown in my Patents 2,176,891 and 2,297,099 and in my copending application Serial No. 649,330, filed February 21, 1946, now Patent No. 2,484,018, and the primary object of the invention resides in the production of improved method and mechanism for performing this operation effectively and producing superior, more uniform and smoother linings that will serve more efiiciently the conductive flow of liquids.

One embodiment of the invention comprises a machine including a carriage adapted to be moved longitudinally through a pipe to be lined and having associated therewith a grout conducting conduit terminating in a projecting nozzle, together with means for rotating the nozzle about the longitudinal ads of the-pipe and pneumatically projecting grout (semi-liquid cementitious mixture) therefrom outwardly onto the innerwall of the pipe. The grout contains light and heavy ingredients mixed with water and it is desirable not only that the grout shall be well and uniformly distributed over the wall but also that the lighter ingredients shall be disposed on and cover the heavier ingredients. An object of the invention consists in the production of improved method and apparatus for performing these functions.

The grout is passed through the conduit and nozzle at high speed and I have discovered that, by disposing the nozzle end portion of the conduit in a curved path, the heavier ingredients are deflected and separated centrifugally to the outside of the grout stream from the lighter ingredients at the inside of the stream. When thus employed in the coating of pipes, the nozzle is so located that it projects the heavier solids in a field relatively wide longitudinally of the pipe axis thereby more uniformly distributing such solids along the pipe wall as the nozzle is rotated and moved therealong. Furthermore, by rotating the nozzle about the pipe axis in a direction advancing the stream over the pipe wall with that portion foremost which contains the heavier ingredients, the heavier ingredients will be projected in advance of and be covered by the lighter ingredients. The production of improved method and mechanism of this nature for the purpose described and of improved and associated troweling mechanism for troweling the mixture to a uniformly smooth surface as it is projected into place comprises a further object of the invention.

These and other features of the invention will be more readily understood and appreciated from the following detailed description of preferred embodiments thereof selected for purposes of illustration and shown in the accompanying drawing, in which:

Fig. 1 is a side elevation of a machine embodying the invention, illustrated as placing a lining on and within a, pipe;

Fig. 2is a fragmentary sectional view taken on line 22 of Fig. 1;

Fig. 3 is a fragmentary plan view of Fig. 2;

Fig. 4 is a view similar to Fig. 2 but showing a modified construction, and

Fig. 5 is a like view but showing a further modified construction.

While certain features of the invention are of relatively wide application and can be employed in theplacing of grout coatings on plane or curved surfaces, the invention is particularly applicable to the lining of large pipes or conduits with cementitious grout and I have in the accom-v panying drawing illustrated the invention in association with a mechanism for performing this function. Such pipes are ordinarily used to convey water or other liquids and it is highly important that the lining shall present a smooth and uniform surface to the liquid flow. Any roughness or lack of uniformity offers resistance to the flow and presents a surface that will accumulate foreign matter and retard the flow. An important object of the invention therefore resides in the production of method and means for constructing a uniform lining having a smooth and unbroken flow surface.

In the drawing I ll indicates a wheeled carriage adapted to pass through a pipe l2 to be lined. The carriage is driven in any convenient manner and the mechanism employed is of the general nature disclosed in my said copending application. A grout conducting conduit I4 is mounted for rotation in housings l5 and I8 on the carriage and is disposed at an elevation locating it at the central longitudinal axis of the pipe. Grouting material is fed to the conduit through a hose connection to pipe 20 threaded into the housing I6.

The nozzle end portion 22 of the conduit is curved outwardly from the longitudinal axis of the pipe I2 as illustrated in Figs. 1 and 3 and thence curved U-shaped to the projecting nozzle 24 which is illustrated in Figs. 1-3 as extending through the axis and disposed radially of the pipe. The grouting material is projected in a stream of air through the conduits 20, H and 22 and comprises a dry mixture of cement, sand and gravel and 1 preferably add the, water to this mixture at the nozzle. A water pipe 28 tapped into the nozzle and mounted to rotate with the conduit I4 is provided for this purpose, water being conducted to this pipe through the housing Hi from a pipe 28.

Supported in the housing l8 for rotation with and extending rearwardly from the conduit I4 is a shaft 30 for supporting the troweling mechanism including a shaft 32 journaled for rotation on the end portion of the shaft 30. A plurality of trowels 34 are carried on arms 36 attached to the shaft 82 as, for example, in the manner specifically described in my said copending application. The conduits i4 and 22 are rotated by a motor 38 through gear connections in mesh with a gear 40 fixed to the conduit I 4, and the shaft 32 is driven as follows. A shaft 42 is mounted to rotate in bearings on flanges 44 and 46 fixed to the shaft 30, a pinion 48 on the shaft 42 is'in mesh with a gear 50 fixed nonrotatably to the housing l8. A pinion 52 on the other end of the shaft 42 is in mesh with a gear 54 fixed to the trowel shaft 32. As will be apparent, the shaft 42 will be rotated as the conduit I4 is rotated and its relative speed of rotation can be varied by employing gears of varying size. A segmental shield 56 carried by the flange 44 in opposed relation to the nozzle 24 serves to prevent splashing of the grout rearwardly of the nozzle. nozzle is provided in or through the shaft 39, as illustrated at 58 and 68 as will be understood.

The operation of the mechanism illustrated in the drawing will now be described. The carriage is continuously moved forwardly through the pipe I at a rate predetermined to produce the desired lining and is under the control of an operator on the carriage. Grouting material is forced by air through the conduits l4 and 22 and is mixed with the proper amount of water at the nozzle and this mixture is projected outwardly of the nozzle as illustrated in the drawing. The shield 56 rotates with the nozzle and is always disposed in opposed relation thereto and prevents rearward splash of grout to the troweling mechanism and troweled surface.

The dry grouting material is air-conveyed at high speed through the conduits l4 and 22 to the nozzle. During passage of this material through the sharply curved conduit 22 the heavier ingredients are deflected and separated centrifugally to the outside of the stream from the lighter ingredients at the inside of the stream. The conduit and nozzle are so arranged that the heavier ingredients are disposed in a field relatively wide longitudinally of the pipe axis whereby more uniformly distributing such solids along the pipe wall as the nozzle is rotated and moved therealong. Furthermore, by rotating the nozzle about the pipe axis in a direction advancing the .stream over the pipe wall with that portion foremost which contains the heavier ingredients, this portion of the stream will be projected onto the surface to be coated in advance of the portion containing the lighter ingredients. As illustrated in the drawing, the nozzle and conduit 22 are so arranged that said outside portion of the stream through the nozzle and for a substantial distance rearwardly thereof is located at one side of a plane parallel with the longitudinal axis of the pipe l2 and passing longitudinally through and parallel with the longitudinal axis of the nozzle. This arrangement is adapted to project the heavier solids through the nozzle in said field Clearance space for the 4 relatively wide longitudinally of the pipe axis and to project the lighter solids on and following the placing of the heavier solids, as illustrated in Figs. 2 and 3, when the nozzle is rotated in the direction indicated by the arrows.

In Figs. 2 and 4 the plane above referred to is disposed horizontally and diametrically through the figure, the heavier ingredients being located above the plane. These ingredients have been disposed to the outside portion of the curved path of the conduit through centrifugal force and the upper portion of the nozzle corresponds to and provides a continuation of this portion of the path and receives the heavier ingredients, as illustrated. It will be apparent that rotation of either the nozzle 24 or the pipe [2 about the longitudinal axis of the pipe, in the relative direction indicated by the arrow in Fig. 2, will advance the sprayed stream over the inside surface of the pipe along a path disposed substantially right angular to said lane.

This projecting of the heavier ingredients through a field relatively wide in the direction of the longitudinal axis of the pipe is a matter of considerable importance. It will be understood that there is a substantial overlapping of each projected layer onto the previous layer as the carriage is traversed along the pipe, and the troweling mechanism immediately follows the nozzle and automatically trowels the exposed top solids to a smooth surface. It will be readily apparent that such distribution of the heavier ingredients in the band relatively wide longitudinally of the pipe results in the production of a lining substantially more uniform in thickness and surface level, and the top coating of lighter ingredients provides a smooth surface. Obviously, a lining of this character is adapted to conduct liquids with maximum efficiency and eliminate the difficulties caused by rough and uneven lining surfaces.

In Figs. 1-3 I have illustrated the nozzle 24 as located at the longitudinal axis of the pipe I 0 being lined whereas in Fig. 4 I have illustrated the nozzle 60 as located rearwardly of the pipe axis. The purpose of thus locating the nozzle 60 is to give sufiicient length of projection to provide the desired spread of material, this arrangement being used in the lining of relatively small pipes having a radius insufficient to provide the necessary projecting length. The pipe 62 and the conduit 64 of Fig. 4 are otherwise substantially the same as above described.

While the projecting nozzle will ordinarily and preferably be located at and disposed radially of the pipe axis (Figs. 2 and 4) it should be understood that such location and disposition are not absolutely essential and I desire it to be understood that the invention is not to be considered as thus limited. In Fig. 5, for example, I have illustrated the nozzle Ill as disposed somewhat to one side of the pipe axis. In such case the projected stream is not truly radial but is sufliciently radial to serve the function of the invention. In Figs. 4 and 5, for example, the nozzles 60 and 10 are located adjacent to the longitudinal axis of the pipe and in Fig. 5 the nozzle 10 is located substantially radially of the pipe and any such location and disposition which will serve the purpose of the invention are considered as well within the scope of the invention. The pipe 12 and conduit 14 of Fig. 5 are otherwise substantially the same as above described.

Heretofore the grouting material has been conducted through a conduit located along the pipe axis and extending ou 'dly therefrom substantially right-angularly to the axis and terminating in a nozzle from which the grout is sprayed onto the pipewail, as illustrated in mysaid co-pending application. In such case the main body of ingredients sprayed from the nozzle, rotated about and moving along the pipe axis,

strike the pipe wall along a line extending spirally 7 around the wall and build up spiral ridges which are diflicult and impossible to trowel to a uniform level. The invention herein described eliminates this difiiculty by spraying the heavier ingredients through a path relatively wide longitudinally of the pipe axis, as illustrated in Figs. 2 and 3. formly distributes the heavier ingredients longitudinally of the pipe wall and provides overlapping layers that can be easily troweled to provide a uniformly level lining on and along the pipe as will be apparent by reference to Fig. 1 of the drawing.

Having thus disclosed my invention what I Such spraying of the grout more uni--' 6 adjacent to and disposed substantially radially of the axis, the outside portion of said path through said opening and for a substantial distance rearwardly thereof being located atone side of a plane parallelwith said axis and the longitudinal axis of the path at the opening, the curved path thence extending rearwardly through and to the opposite side of the plane and continuing rearwardly therefrom for a substantial distance substantially right angularly to the plane and from thence to the pipe axis portion.

of the path, said stream of solids being conducted through said path at a speed sufficient centrifugally to move the solids to the outside portion of the path, adding a stream of water to the solids to form the same into a semi-liquid mixture, and projecting the mixture from the opening'while rotating the stream about the pipe claim as new and desire to secure by Letters of the mixture.

2. The process of coating a surface with a cementitious wet grouting mixture containing light and heavy ingredients, which consists in passing the mixture in a stream at high speed through a sharply curved path and thereby causing the heavy ingredients of the mixture to be deflected centrifugally to the outside of the stream, spraying the stream thus modified against the surface while causing the stream and surface to have relative movement advancing the stream over the surface with that portion foremost which contains the heavier ingredients of the mixture, thereby projecting the heavy solids first and covering them with the light solids, and immediately troweling the exposed top solids of the projected mixture to a.

smooth surface.

3. The process of coating the inner wall of a tubular shell with a cement wet grouting mixture containing light and heavy ingredients, which consists in passing the mixture in a stream at high speed through a sharply curved path and thereby causing the heavy ingredients of the mixture to be deflected centrifugally to the outside of the stream, and spraying the stream thus modified against the wall while causing the stream and wall surface to have relative movement about the longitudinal axis of the shell in a direction advancing the stream over the wall surface with that portion foremost which contains the heavier ingredients of the mixture.

4. A method of coating the inside surface of a pipe with a semi-liquid cementitious mixture including solids, which consists in conducting a stream of the solids to and along the longitudinal axis of the pipe and thence through a confined and sharply curved path outside of said axis to a restricted projecting opening located axis, said operation being adapted to project the solids through the opening in a field forwardly of said plane and in a stream relatively wide longitudinally of the pipe axis.

.5.,Apparatus for coating the inside surface of a pipe with a semi-liquid cementitious mixture including solids, comprising a conduit adapted to be disposed axially of the pipe, a nozzle disposed substantially radially of the conduit and adjacent to its longitudinal axis, a curved conduit disposed outside of said axis with its ends in communication with the nozzle and the first-named conduit, the portion of the nozzle corresponding to the outermost portion of the curved conduit being located to one side of a plane parallel with said axis and passing longitudinally through and parallel with the longitudinal axis of the nozzle, a pipe in communication with the opening in said conduits for conducting a stream of water to said solids therein, and means for rotating the curved conduit and nozzle about said axis, said solids being disposed by centrifugal force to said outermost portion of the curved conduit and the nozzle being located to spray said solids therefrom in a path relatively wide longitudinally of the pipe axis.

6. The apparatus defined in claim 5 in which said water conducting pipe communicates with said opening at a point between the curved conduit and the free end of the nozzle.

'1. The apparatus defined in claim 5 plus trowel supporting means supported on the apparatus for rotation with the nozzle about/said axis, and a trowel carried by said means in position to trowel said mixture after it is projectedonto the first named pipe.

8. 'The apparatus defined in claim, 5 in which said portion of the nozzle corresponding to the outermost portion of the curved conduit and said outermost portion of the conduit adjacent to and for a substantial distance rearwardly of the nozzle is disposed substantially parallel with and at said one side of said plane.

9. Apparatus for coating the inside surface of a pipe with a semi-liquid cementitious mixture including solids, comprising a conduit adapted to be disposed axially of the pipe, a nozzle disposed substantially radially of the conduit and adjacent to it longitudinal axis, a curved conduit disposed outside of said axis with its ends in ing through the nozzle exit and through and.

along said axis, a pipe in communication with the opening in said conduits for conducting a force to said outermost portion of 'the curved conduit and the nozzle being located to spray said solids therefrom in a path relativelywide longitudinally of the pipe axis.

l0.'A method or coating the inside surface of a pipe with a semi-liquid cementitious mixture including solids, which consists in conducting a stream of the solids to and along the longitudinal axis of the pipe and thence through a confined and sharply curved path outside of said axis to a restricted projecting opening located adjacent to and disposed substantially radially of the axis, theoutside portion of said path through the openingand for a substantial distance rearwardly thereof being located at one side of a plane parallel with said axis and the longitudinal axis of the path at the opening, the curved path thence extending rearwardly through and to the opposite side of the plane and continuing rearwardly therefrom for a substantial distance substantially right angularly to the plane and from thence to the pipe axis portion of the path, said stream of solids being conducted through said path at a speed suflicient to move them centrifugally on the curve to the outside portion of the path, adding a stream of water to the solids to form the same into a semi-liquid mixture, and projecting the mixture from the opening while rotating the stream about the pipe axis in a direction substantially right angularly to said plane, said operation being adapted to project the solids through the opening in a field relatively wide longitudinally of the pipeaxis.

JOHN M. CROM.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 9 2,099,076 Perkins Nov. 16, 1937 2,168,917 Perkins Aug. 8, 1939 2,185,570 Ridley Jan. 2, 1940 2,297,099 Crom Sept. 29, 1942 

